Field of the Invention
The present invention relates to an arrangement for counteracting stress in a portion of an implant provided with an internal socket extending in said portion, via which the implant can be tightened by means of a turning tool or turning instrument which has first lateral surfaces that can cooperate with corresponding second lateral surfaces in the internal socket.
Description of the Related Art
It is already known to anchor implants in holes in the jaw bone with the aid of instruments or tools. The implant can be fitted in a threaded hole or can be of the self-tapping type. It can be screwed in using said internal socket for the tool, and the present invention relates to this type of implant. Reference is here made in quite general terms to implants and methods which are generally known in dentistry in connection with screwing-in of implants.
An implant with an internal socket affords advantages, such as easier connection of spacer elements and other components to the implant. The necessary implantation force/turning force can, however, be relatively high, and the material thickness of the implant is often low, especially in the case where the implant is of small dimensions. This can result in the implant being deformed or being at risk of breaking at the site where the turning force is applied. One reason for this happening is that the internal socket, which has a non-round geometry, is often a polygon or some other geometrical figure that results in outwardly directed forces when the implant is being turned into its position. This results in stresses in the implant which act outward and which force the material out and apart. The most obvious way of improving this situation would be to change the non-round geometry so that the outwardly directed forces were reduced. However, this can often be difficult to do in practice, for production technology reasons among others. In established implant systems, these geometries are already defined, and a large range of known ancillary components are based on these geometries. Changing the geometry would therefore be associated with considerable costs and would cause great technical problems. The invention aims, inter alia, to solve these problems.
Another type of load which can occur on a portion with said socket is a bending load, and this can occur either as the sole problem or as a problem in combination with the disadvantages of the turning forces. If one wishes to change the direction of the implant during implantation thereof, or if the angled handpiece or wrench is not applied properly to the tool/implant, a bending force is exerted which will deflect the implant and which, in addition to producing undesired deformation, can also lead to fracturing of the implant portion/flange which has the socket. The invention also aims to solve this problem.